The present invention relates to a surgical operation apparatus and a manipulator used in the surgical operation apparatus. In particular, the present invention relates to a medical manipulator.
Japanese Patent Laid-Open No. H11(1999)-267133 discloses an example of a thermal procedure in which a body of a patient is transfixed with a high frequency treatment tool, and a diseased area of the body cavity is treated while observing the diseased area by use of a diagnosis apparatus such as a MRI apparatus, a supersonic scanner and an endoscope. In this procedure, an abdomen of a patient is inflated by means of a pneumoperitoneum method, and a linear treatment applicator and an endoscope are inserted exogenously. While observing markers attached to the treatment applicator by use of an MRI apparatus, the treatment applicator is introduced to the diseased area, which is then treated.
Japanese Patent Laid-Open No. 2003-339664 discloses another example of the thermal treatment. In this treatment, markers which can be recognized by an infrared camera are attached to a rear end of a puncture needle of a treatment tool. In accordance with position information about a puncture needle imaged by the infrared camera and with images acquired by the MRI apparatus, the treatment tool is introduced to the diseased area.
U.S. Pat. No. 6,394,998 and Japanese Patent Laid-Open No. 2004-122286 disclose an example that a medical manipulator is used for treatments. In this manipulator, joints are driven by wires. In consideration of safety and compactness, a driving actuator is prevented from being directly attached to the joint mechanism. In a manipulator disclosed in a U.S. Pat. No. 6,394,998, a top end joint and a surgical device joint provided distally of the top end joint are pivoted and opened and closed by use of wires. In a manipulator disclosed in a Japanese Patent Laid-Open No. 2004-122286, transmission lengths and phases of driving wires are maintained constant regardless of a change of an angle of the joint by use of two rolling members.
Since the conventional surgical devices for thermal treatments, disclosed in Japanese Patent Laid-Open No. H11(1999)-267133 and Japanese Patent Laid-Open No. 2003-339664 have a linear shape, it is sometimes difficult that the surgical device approaches a target diseased area while avoiding organs, blood vessels, and so on (hereinafter called obstacles) which are not diseased and thus cannot be injured. Additionally, a puncture attitude of the surgical device is limited. When the surgical device is introduced to a diseased area, a position of a top end of the surgical device is recognized by use of MRI tomographic images. In some cases, it takes long time to find markers placed near the top end of the surgical device from many MRI tomographic images.
A surgical device attached to a top end portion of a medical manipulator is required to be compact and to have a plurality of degrees of freedom. In the manipulator disclosed in U.S. Pat. No. 6,394,998 and Japanese Patent Laid-Open No. 2004-122286, when driving power is transmitted from a bending joint to a top end joint next to the bending joint, the driving power is transmitted from the bending joint to a surgical device by use of wires. When the driving power is transmitted through the bending joint by use of wires, the wires may be fatigued and worn to brake. A joint mechanism such as a surgical device using wires having thin diameters needs to be often maintained.